Methods for unloading a roll of material are used frequently, but by no means exclusively, in, for example, web-fed rotary printing presses to remove finished or partially used rolls of material from a roll changer. To ensure a reliable stripping of the roll of material from the axle journals of the roll changer, stripping devices, such as stripper rings, are provided in generally known roll changers.
A method for unloading a roll of material from a roll changer of a web-fed rotary printing press is described in DE 101 50 810 A1. In this method, the stripping devices are actuated, in a position-controlled or a position-regulated manner. As the axle journals of the roll arms are being moved apart, the stripping devices move along the same path as the roll arm, but in the opposite direction relative to the axle journals. As a result, the residual roll does not change its position during the separation of the roll arms and the associated stripping of the residual roll from the axle journals of the roll arms.
WO 02/40387 A1 describes a device for producing sleeveless paper rolls. In order to change such paper rolls, the two support journals are pulled back simultaneously.
U.S. Pat. No. 4,903,910 A describes a process for unloading a roll of material in a roll changer. A distance between the support elements is greater than the length of a sleeve. For the safe unloading of the sleeves, strippers are provided.
EP 0 391 061 A1 describes a device for aligning a new roll of material. An alignment device presses against the roll of paper, and thus can move an unlocked transport car on a sliding platform.